Abstract
Background: We have previously found an inverse association of bacterial diversity
with childhood asthma. It remains unclear whether certain bacteria account
for the protective effect.
Methods: The high variability of the bacterial 16S rRNA gene allows assessing
diversity and specificity of bacterial communities by single-strand configuration
polymorphism (SSCP). DNA was extracted from mattress dust samples of 489
school-age children from rural and suburban regions in Germany. A fragment
of the bacteria-specific 16S rRNA gene was amplified by PCR, digested to single-strand
DNA, and subjected to electrophoresis. The resulting band patterns
reflect the underlying DNA sequences. The individual bands were tested for
associations with asthma, hay fever, and atopy in quantitative and qualitative
multivariable analyses. Significantly associated bands were isolated and
sequenced. The sequences were compared to a database, and distinct bacteria
were identified.
Results: Seven of 76 independent bands were found to be inversely associated
with asthma, atopic sensitization, and hay fever with odds ratios ranging from
0.17 to 0.73. The bands contained the sequences of Acinetobacter sp., Lactobacillus
spp., Neisseria spp., Staphylococcus sciuri, Jeotgalicoccus sp., Corynebacterium
spp., and others.
Conclusions: In a diverse microbial environment, certain bacteria may account
for the protective effect on the development of asthma and atopy.